Packaging machine and method of packaging products

ABSTRACT

A packaging machine ( 1 ) comprises a device for the formation of a tube ( 5 ) of wrap material into which a succession of products ( 6 ) can be inserted; a sealing device ( 7 ) being active on said tube ( 5 ) to make a succession of seals ( 23 ) transverse to the direction of advancement “A” of tube ( 5 ) and to define a corresponding succession of pockets ( 11 ) for holding the products ( 6 ); an air-removing device ( 13 ) being active on each pocket ( 11 ) in correspondence of a respective aperture ( 25 ) to produce a vacuum inside each pocket ( 11 ); an additional sealing device ( 22 ) operatively located at least in correspondence of the air-removing device ( 13 ) for isolating said aperture ( 25 ) and hermetically sealing the pocket ( 11 ).

TECHNICAL FIELD OF THE INVENTION

The present invention refers to a packaging machine and a method of packaging goods. In particular, the machine and method according to the present invention applied to the packaging of food products, for example oven products, cold pork meats and others. In the description that follows, reference is made to such application with no detriment to generalization.

BACKGROUND ART

Packaging machines are known to package goods starting from a tape of coiled plastic material. The tape unwound from the coil is made to move forward in a feeding direction toward a tube-forming member of plastic material operatively located downstream of the coil. In particular, the tape is wound around such forming member to define the said tube by superimposing two side edges of the tape. Moreover, the tube is completed by longitudinally welding said side edges to each other by means of a first welding means located in correspondence of the forming member.

The packaging machines of known type comprise a second welding means which is made to act on the tube to close it completely by welding in correspondence of a section transverse to a tape-feeding direction, so as to define a pocket. In particular, the second welding means operates a succession of transverse weldings on the tube, thereby defining a corresponding succession of pockets.

A product to be packaged is then inserted into the tube in correspondence of the forming device. More in detail, one product is inserted within each pocket. Subsequently to the insertion of each product, the second welding means operates a welding on the tube so as to close the pocket in which the product has been inserted and, at the same time, to define the successive pocket.

The closed pocket defines therefore a package which is detached from the tube by means of a blade.

The above described operations take place continually on the tube, which makes the known packaging machines unsuited for mass-packaging food products.

Such packaging machines of known type exhibit a major disadvantage inasmuch as they cannot make vacuum packages, that is, packages able to preserve food products over an extended period of time.

To carry out such operation, devices are available on the market for creating a vacuum and sealing the packages. Such devices comprise a container hermetically closable by a lid. A bag holding a product to be packaged is introduced into the container, the latter being connected to a pump for sucking air. Upon inserting the product-holding bag into the container, the operator closes the lid and starts the pump to create a vacuum inside the container. Such devices further comprise a welding means, located in correspondence of the lid and able to seal the bag.

The use of such devices exhibit a major disadvantage inasmuch as they cannot operated continually and require instead to perform a work of discrete type. In particular, an operator has to introduce the product-holding bag into the container and then extracting the same therefrom. These devices result therefore unsuited for packaging a large quantity of food products.

DISCLOSURE OF THE INVENTION

In this context, the technical task of the present invention is to provide a packaging machine and a method of packaging products without the above cited drawbacks.

In particular, the object of the present invention is to provide a packaging machine and a method of packaging food products by vacuum operation for mass-production.

This object is substantially achieved by a packaging machine and a method of packaging products according to what is disclosed in one or more of the appended claims.

Further characteristics and advantages will appear more clearly by a detailed description of a preferred and non-exclusive embodiment of a packaging machine and a method of packaging products according to the invention.

Such description is given with reference to the attached FIG. 1, also having merely exemplifying and thus non-limiting purpose, which shows a schematic side view of a packaging machine according to the present invention.

With reference to FIG. 1, numeral 1 designates in the whole a packaging machine according to the present invention.

Such packaging machine 1 allows packaging products starting from a taper 3 of wrap material. In particular, such tape 3 is wound into a coil 2. The wrap material may, in case of enclosures for food products, be a film of polymeric type. The wrap material may further comprise an internal or external coating suited for the product to be packaged.

Besides, such wrap material is heat-sealable. The coil 2 is unwound to provide the said wrap material 3. The tape 3 moves then forward along a direction of advancement “A”.

The packaging machine 1 includes a tube-forming device 5. Such forming device comprises driving means (not shown) for the tube 5, which move the latter along the said direction of advancement “A”.

The forming device further comprises a tubular forming member 4 of known type, operatively located downstream of the coil 2. The tape 3 of wrap material is then wound around such forming member 4 to define a tube 5 by superimposing the edges of tape 3. In the preferred embodiment, the tube 5 is completed by welding the edges of tape 3 to each other in correspondence of the forming member 4. In an alternate embodiment (not shown) the forming device forms the tube 5 by joining the edges of two tapes 3 unreeling from a respective coil.

The tube 5 then transits in correspondence of a first sealing device 7 locate downstream of the forming member 4. In particular, such sealing device 7 is made to act on the tube 5 for producing a succession of seals 23 transverse to the direction of advancement “A” of tube 5. In greater detail, each seal 23 extends over the whole width of tube 5 so as to tightly close a section of tube 5 transverse to the direction of advancement “A”. In this way, the sealing device 7 defines a succession of pockets 11 for the insertion of the products 6. In other words, each pocket 11 results defined by at least a relevant seal 23. Such pocket 11 results open, thereby allowing the insertion of the product 6 through an insertion section 5 b of tube 5 and preferably located in correspondence of the forming member 4. In detail, the forming member 4 exhibits an inlet mouth 4 a in correspondence of which the insertion section 5 b is disposed.

It should be noted that each seal 23 defines a respective pocket 11 to be filled with a product 6, and closes the pocket 11 previously filled with another product 6.

In the described embodiment, the sealing device 7 is a welder preferably shaped as a bar of a length at least equal to the width of tube 5.

The packaging machine 1 comprises a device 13 for the removal of air from tube 5. In particular, the air-removing device 13 is made to act on each pocket 11 in correspondence of an aperture 25 to produce a vacuum inside each pocket 11. In other words, the air-removing device 13 is active on the pocket 11 to take out substantially all the air held therein. Such air-removing device 13 is preferably located to operate downstream of the sealing device 7. The operation of the air-removing device 13 is best illustrated herebelow.

Advantageously, the packaging machine 1 comprises a blocking element 10 located to operate downstream of the sealing device 7. In particular, such blocking element 10 is operatively located between the sealing device 7 and the air-removing device 13. Such blocking element 10 is activable on the tube 5 to retain the latter and hermetically isolate the pocket 11 which holds the product 6. In greater detail, the blocking element 10 operates in cooperation with the air-removing device 13 by temporarily closing the pocket 11 during the removal of air.

The blocking element 10 comprises a press 12 movable away from the tube 5. Said press 12 being also movable close to the tube 5. The press 5, thereby, is commutable between an operating configuration in which it engages the tube 5 to isolate the pocket 11, and a release configuration in which it is cleared of tube 5.

In the preferred embodiment, the air-removing device is activated when the blocking element 10 is active on tube 5. In other words, the air-removing device 13 is active when the press 12 is in operating configuration.

In the preferred embodiment, the air-removing device 13 comprises a hollow needle 14 for perforating the pocket 11 and defining the aperture 25.

The air-removing device 13 further comprises a suction member 15 connected to the needle 14 to remove the air from pocket 11. In particular, such needle 14 is able to move close to and away from the tube 5. In detail, the needle 14 is movable in such a way as to perforate the pocket 11 by entering therein and sucking the air therefrom and, similarly, to come out from the pocket 11 upon completion of suction.

In particular, in the described embodiment, the suction member 15 comprises a hollow cylinder 16 connected to the needle 14 in correspondence of a base 16 a. A piston 17 is inserted into the cylinder 16 and is movable away from the base 16 a to suck air from tube 5 through the needle 14.

Preferably, the step of inserting the needle 14 inside the pocket 11 takes place prior to the descent of the blocking element 10 onto the tube 5; in this way, the introduction of needle 14 into the surface of tube 5 is made easier by said surface being not under stress.

The packaging machine 1 also comprises a further sealing device 22 operatively located downstream of the air-removing device 13. Such sealing device 22 is movable to and away from tube 5, when the press 12 is in operating configuration, to define an additional seal on pocket 11. Such additional seal isolates the aperture 25 by hermetically sealing the pocket 11 to prevent the air from entering through the same aperture 25. In particular, the additional seal divides the tube 5 into an air-removing region 19 a and a storage region 19 b for holding the product 6. In other words, the air-removing region 19 a and the storage region 19 b for holding the product 6 define the pocket 11. In greater detail, the additional seal runs throughout the width of the tube 5 and is a segment parallel to the seals 23 formed on tube 5. In the preferred embodiment, the aperture 25 is formed by the needle 14 onto the air-removing region 19 a.

The additional sealing device 22 comprises a welder 20. In the described embodiment, the welder 20 is preferably shaped as a bar of a length at least equal to the width of tube 5.

Since the tube 5 is made of a thermoweldable material, the welder 20 operates on the pocket 11 by heat-sealing it.

A further embodiment provides for the use of an upper welding bar which, by entering in contact with a corresponding lower welding bar, carries out the transverse welding.

The packaging machine 1 also comprises cutting means (not shown) for separating the pocket 11 from tube 5 in correspondence of each seal 23.

Said cutting means preferably include a stationary blade (not shown) located in correspondence of the sealing device 7 so that the latter, when actuated, will enter in contact with the blade. Consequently, the blade is made to act preferably simultaneously to the sealing device 7. In this way, the just filled pocket 11 is separated from the tube 5 and a fresh pocket 11 to be filled is defined.

Advantageously and similarly to the device 22, provision may be made for the welding device 7 to cooperate with a cutting device to remove the portion of tube which includes the hole 25.

The packaging machine 1 further comprises a work plane 21 able to be inclined with respect to a preferably horizontal reference direction In particular, the blocking element 10, air-removing device 13, sealing device 7 and additional sealing device 22, are active in correspondence of the work plane 21.

Preferably, the packaging machine 1 may comprise a feeding device 26 for products 6, which is operatively located upstream of the forming member 4. The feeding device 26 is disposed in correspondence of the work plane 21 so that the products 6 exiting from the same feeding device 26 are laid onto the inclined work plane 21. Advantageously, in this way, the products 6 move by gravity along the work plane 21 toward the inlet mouth 4 a of forming member 4 to enter the tube 5 and, in particular, the pocket 11 to be filled.

In an alternate embodiment, the work plane 21 is horizontal and the packaging machine 1 comprises a driving device (not shown) to insert the products into the tube 5 through the inlet mouth 4 a.

In greater detail, the sealing device 7, additional sealing device 22 and blocking element 10 are connected above the work plane 21. In the preferred embodiment, the air-removing device 13 is located sideway of the work plane 21. In an alternate embodiment, the air-removing device 13 is located above the work plane 21.

Moreover, the packaging machine 1 comprises means for adjusting the inclination of the work plane 21. It is thus possible to change the angle of inclination of the work plane 21 with respect to the reference direction “B”. This makes it possible to suitably reduce the speed of descent of product 6 thereby avoiding risks of damage. It is also possible to increase the speed of product 6 should these risks be not present, by increasing the number of products packaged by the machine 1 per unit of time.

Besides, it is an object of the present invention to provide a method of packaging products 6. The method comprises the steps of predisposing the tube 5 of warp material. Thereafter, the succession of transverse seals 23 are formed on the tube 5 so as to define a succession of pockets 11 starting from the tube 5. Once each seal 23 is carried out, each product 6 is inserted into the pocket 11 just defined on tube 5 by the corresponding seal 23.

Once the pocket 11 is filled, the tube 5 is blocked and the said pocket 11 is hermetically and simultaneously isolated. The pocket 11 is then perforated to define the aperture 25, preferably in correspondence of the air-removing region 19 a (upper portion of pocket 11). Air is then drawn out of pocket 11 through the aperture 25, preferably until all the air is removed therefrom. In particular, the removal of air is carried out during the step of hermetic isolation of pocket 11.

Upon completion of removal of the air, a further seal is formed on the pocket 11 so as to separate the air-removing region 19 a from the storage region 19 b.

In particular, said further seal of pocket 11 is formed during the step of hermetic isolation of same pocket 11, preferably by thermowelding. In greater detail, the operation of making said further seal onto the pocket 11 ends up during the step of hermetic isolation of pocket 11. In other words, the step of temporarily and hermetic isolation of pocket terminates successively to the formation of said further seal.

Each seal 23 closes the pocket 11 being filled up, defines one package and at the same time the base of the successive pocket 11.

The method also comprises a cutting step to separate the finished package from the successive pocket 11. Such cutting step preferably takes placed concurrently to the sealing step.

The present invention reaches the specified object and achieves major advantages. In particular, this machine is able to package mass-produced items in vacuum condition so as to package a large quantity of food products in a short time.

Moreover, such machine is able to carry out all the operations necessary for packaging a vacuum product with no need for operator's intervention.

The packaging machine according to the present invention is also able to package products of whatever length, latter being limited merely by the extension of the coiled tape. 

1-15. (canceled)
 16. Packaging machine having a device for the formation of a tube of wrap material into which a succession of products can be inserted; a sealing device being active on said tube to make a succession of seals transverse to the direction of advancement “A” of tube and to define a corresponding succession of pockets for holding the products; an air-removing device being active on each pocket in correspondence of a respective aperture to produce a vacuum inside each pocket; an additional sealing device operatively located at least in correspondence of the air-removing device for isolating said aperture and hermetically sealing the pocket, said machine comprising a blocking element, operatively located between the sealing device and the air-removing device; said blocking element being activable on said tube to retain it and hermetically isolate the pocket holding the product, said air-removing device being further active when said blocking element is active on tube.
 17. Machine according to claim 16, wherein said blocking element comprises a press movable away from and close to said tube for commuting between an operation configuration, in which said press engages said tube for isolating said pocket, and a release configuration in which said press is clear of said tube.
 18. Machine according to claim 17, wherein said additional sealing device comprises a welder movable away from and close to said tube when said press is in operation configuration, said tube being, at least in part, made up of a thermoweldable material.
 19. Machine according to claim 16, wherein said air-removing device comprises a hollow needle to pierce each pocket and to define said aperture, and a suction member connected to the needle for removing the air from said pocket.
 20. Machine according to claim 16, further comprising a work plane which is inclined with respect to a reference direction, said sealing device and said additional sealing device being active in correspondence of said work plane.
 21. Machine according to claim 20, further comprising means for adjusting the work plane to change an angle of inclination of said work plane with respect to the reference direction.
 22. Machine according to claim 16, wherein said sealing device and said additional sealing device comprise an upper welding bar and a lower welding bar movable close to and away from to each other to carry out said transverse seal on said tube.
 23. Method of packaging products, comprising the steps of a) predisposing a tube of warp material; b) carrying out a succession of transverse seals on said tube to define a corresponding succession of pockets therein; c) inserting a product into each pocket; perforating each pocket to define an aperture; d) removing air from each pocket through the respective aperture; e) forming an additional seal on said pocket to isolate said aperture f) hermetically sealing the pocket and g) hermetically isolating the pocket holding the product; said step of removing air from said pocket being carried out during the step of hermetic isolation of pocket.
 24. Method according to claim 23, wherein said step of forming an additional seal on said pocket is carried out during the step of hermetic isolation of pocket.
 25. Method according to claim 24, wherein said step of forming an additional seal on said pocket terminates during the step of hermetic isolation of pocket.
 26. Method according to claim 23, wherein said step of forming an additional seal on said pocket is carried out subsequently to the step of removing air from said pocket.
 27. Method according to claim 23, wherein a step of forming a transverse seal on said tube is carried out subsequently to the step of forming an additional seal on said pocket.
 28. Method according to claim 23, wherein a step of forming a succession of seals and said step of forming an additional seal on said pocket are carried out by thermowelding. 